LOS ANGELES — On Saturday I went to a symphony hall and had an experience unlike any I’ve had before.

At 11:30 p.m., a couple thousand people stood and cheered for the lush and loud art-rock band Sigur Ros. Many had filed into Walt Disney Concert Hall here nearly five hours earlier, for some new chamber works from Iceland, ending with the final piece fading away, faint strings mingling with the players’ gentle humming. During the evening, the Los Angeles Philharmonic joined Sigur Ros for a set, and the orchestra on its own played both a very recent work and a mad rarity from 1930, Jon Leifs’s roaring Organ Concerto.

Oh, and there was an a cappella choir, too.

The marathon evening was the climax of the Philharmonic’s two-week Reykjavik Festival, an exploration of the cross-genre pollinations burbling along in Iceland of late. But with five shows in one, Saturday’s concert felt like a festival unto itself. Sprawling and exhausting, a mix of old and new, pop and classical, amazing and good and well-intentioned-but-sigh-not-so-great, it summed up the L.A. Phil, as the orchestra is universally known, in all its inimitably ambitious glory.

“The ascendancy of the Los Angeles Philharmonic is the salient event in American orchestral life of the past 25 years,” Alex Ross wrote in The New Yorker a few weeks ago.

I’d go further: The Los Angeles Philharmonic is the most important orchestra in America. Period.

As it prepares to celebrate its centennial in 2019, the Philharmonic puts more energy into new work than any other orchestra. It presents a greater sense of the diversity of today’s music and its creators than any other orchestra. It ties its mission to education and social justice in its city more than any other orchestra. And, yes, more than any other orchestra, it combines a commitment to the future with a fresh eye on the past.

Why is all this worth mentioning just now? Because the Philharmonic is facing an unexpected and not altogether welcome transition. Deborah Borda, the leader who guided an already daring institution to new heights over the past 17 years, announced last month that she was leaving to try and work some magic on the struggling New York Philharmonic.

In Los Angeles, Ms. Borda completed the soaring Frank Gehry-designed Disney Hall, which had been languishing before her arrival; gave new vigor to the Hollywood Bowl, owned by the orchestra and now a reliable cash cow; quintupled the endowment; and hired Gustavo Dudamel as music director when he was a fledgling and made him a star. With orchestra subscription bases faltering, Ms. Borda’s Los Angeles Philharmonic rethought its season as a series of events and festivals, each night needing to stand on its own, to sell itself.

Going through the calendar for next season and marking the events I don’t just want to see but feel I really need to see — the ones I would fly across the country for in a heartbeat — I ended up with more than 10.

A lot of that is contemporary work, major new projects from Annie Gosfield, Andrew Norman, Ted Hearne, Esa-Pekka Salonen and other composers I cherish; another pop-classical festival, this one devoted to Mexico. But not all: Leonard Bernstein’s “Chichester Psalms” as a curtain raiser for Beethoven’s Ninth? Bruch’s Concerto for Two Pianos? A Peter Sellars staging of “Das Paradies und die Peri” to close a Schumann cycle? Sign me up.

As Mr. Ross wrote in The New Yorker, when it comes to creativity and diversity, the orchestra is mainly competing with itself. While Ms. Borda’s new orchestra in New York has dived gamely into contemporary pieces and the occasional theatrical presentation under its departing music director, Alan Gilbert, both Contact!, its perpetually wilting new-music series, and its NY Phil Biennial of fresh work have lacked Los Angeles’ exuberant focus.

Every orchestra delves into canonical composers like Tchaikovsky and Rachmaninoff, but the New York ensemble’s festivals don’t range any further. David Geffen Hall at Lincoln Center, in its current bland-shoebox form, doesn’t inspire unconventional thinking, as Disney Hall does; many of the New York Philharmonic’s exciting offerings take place outside its stodgy home. And the future holds worries: New York’s next conductor, Jaap van Zweden, has made his name with vigorous, even pushy renditions of the standards, not with unusual ideas about repertory or eagerness to reconsider the very nature of the orchestra. (To be fair, when he arrived in Los Angeles Mr. Dudamel wasn’t known for his originality, either.)

Not everything is perfect here in California, of course — not even the Reykjavik Festival, clearly conceived with love by Chad Smith, the orchestra’s programming prodigy; the composer Daniel Bjarnason; and Mr. Salonen, Mr. Dudamel’s predecessor at the Los Angeles Philharmonic’s podium. When it accompanied Sigur Ros, the orchestra was mostly swamped by a band that’s already symphonic in its blossoming sweep. And though the band’s layering of velvety noise and Jonsi Birgisson’s ethereal wail is always alluring, a little elegiac ache goes a long way.

The less said, the better about the concert on Monday evening that ended the festival proper. (“Björk Digital,” a VR video extravaganza that sounds suspiciously similar to part of that gamin pop star’s woeful 2015 retrospective at the Museum of Modern Art, has been tacked on, May 19 to June 4.) When Mr. Ross tweeted his piece about the orchestra’s ascendancy, someone replied: “Programming trendy trance & cultish minimalists doesn’t make an orchestra ‘great’ by pandering to a dumbed-down audience.”

This comment caught my eye just hours after Monday’s program, which was like that sour sentiment, come to life. The first half offered a genial but dully messy immersion in the musicians’ collective that has sprung up around the Icelandic record label Bedroom Community, founded in 2006 by the composer and producer Valgeir Sigurdsson. The second half, slicker but emptier, found Johann Johannsson, best known for his film scores, joined by members of the ensemble ACME in an unbroken hour-plus of defanged Muzak-Minimalism.

You win some, you lose some. That’s to be expected when it comes to art. What’s more surprising is the one element missing from America’s most innovative orchestra: Where is the digital access to what it creates?

Those of us who can’t be in Los Angeles every weekend want — we need! — a record of the remarkable things going on here. The Detroit Symphony Orchestra, its budget a quarter of the Philharmonic’s, was forced to rethink its musicians’ contract in the wake of a strike a few years ago and now is more or less the only American orchestra with a real platform for webcasting and archiving its performances.

Will the West Coast follow the Rust Belt on this one? I hope so. It tells you everything you need to know about the Los Angeles Philharmonic that I’m so desperate to hear it.

I was lucky enough to enjoy the LAPO in the Musikverein in 2011, when they were conducted by "The Dude". Wonderful orchestra. Only a short number of weeks thereafter I saw the NYPO and the Chicago band; the program at the Musikverein has never equalled that year. I'm presently looking at next year's offerings from March to June and there's not so much to become excited about. The Cleveland, Munich and Philadelphia orchestras and the English Baroque Soloists/Gardiner are scheduled to play. But I can do without Franzie Welzer-Most (Das tut mir leid; kein umlaut). (There's a complication for us; our landlady may have died as I've tried to contact her without success. In 2015 she was already quite ill with lung cancer and only just 50 years of age!)

Zachary Woolfe wrote:The Los Angeles Philharmonic is the most important orchestra in America. Period.

Nonsense. Any such claim for that orchestra ended with the departure of Esa-Pekka Salonen, with the "period" provided by the departure of Deborah Borda. If there was ever any merit to his claim, Woolfe is making it eight years too late.

Anyone who is interested in the actual program of this Reykstravaganza should check the link to the article which was provided by Len below the text (from which he admirably edited every caption and sidebar so that we would not be misled, confused, or otherwise discommoded. ) There are a couple of links there to the actual content of the program.

For everything you never wanted to know about the Disney Hall organ, here is the link. Check out the stop list (two words, not one) and you will see that there is a division called "llamarada." No, this does not mean that the pipes are designed to look like a parade of llamas, but rather according to Google means "flare" or "blaze." I can't think of a standard division name in any language that corresponds, although the fact that it contains the obligatory vertical trumpet gives a hint of its character.

>There's a complication for us; our landlady may have died as I've tried to contact her without success. In 2015 she was already quite ill with lung cancer and only just 50 years of age!

Belle is that a landlady in LA-were you thinking of coming to the US? Sorry to hear about her condition. Regards, Len

She has been our landlady in the 5th District of Vienna (Margareten); we've stayed there for two long stints already. The plan is to return to Vienna early-ish next year but I cannot seem to contact her. She's a wonderful woman and her ailing mother was involved in the theatre in Vienna around WW2 and told us amazing ancedotes about the plays she was involved in (production staff) and the actors she knew, which included Kurt Jurgens (whom you might remember from films).

It's been so long since we were in Vienna-how wonderful if you can get there again-we'll be traveling to London late next month-haven't been there since 2005. Our oyster cards are on their way to us for the public transportation. Regards, Len

Alex Ross wrote:The L.A. Phil’s 2017–18 season, just announced, is so far ahead of that of any rival, in America or around the world, that the orchestra is mainly competing with itself. Close to half of the featured composers are contemporary.

Ross and Woolfe called it just about right, in my opinion. I found more than two dozen concerts in the 2017-18 LAPO season I'd like to hear, a slew of them premieres. With its innovative programming, LAPO may be the most interesting major orchestra in America today.

Ross and Woolfe called it just about right, in my opinion. I found more than two dozen concerts in the 2017-18 LAPO season I'd like to hear, a slew of them premieres. With its innovative programming, LAPO may be the most interesting major orchestra in America today.

Just today I watched a documentary on an art center and person I never even heard of-from the show it seems Orange County south of LA has become quite big-I saw the philanthropist segerstrom talking to Renee Fleming. They mentioned work between him and Carnegie Hall. Regards, Len